This invention relates to a sheet-type membrane switch that has a rotary motion detection function. Switches having a rotary motion function have come into wide use recently in remote controls for editing and program setting of VCRs, CD players, video disks, and DATs.
Until now, switches with a rotary motion function used for the applications mentioned above have had an inner shaft with a rotary motion function and an outer shaft with a shuttle function. The basic mechanism of a switch with a rotary motion function such as this is its rotary encoder. For example, in rotary motion mode, such a switch can send 16 codes from its four output terminals. Each output terminal sends a binary signal, and a specified control code can be sent from within a fixed time interval.
The problem with a switch of this type is that, because of its complex mechanical structure, it is difficult to manufacture in a small size and at a low cost. Thus the challenge, met by the present invention, is to create a thin, low-priced digital switch by using an electrical structure and software processing to replace, as much as possible, the complicated mechanical structure of conventional switches having a rotary motion function.